1. Field of Use
This invention relates generally to means for storing and connecting a jib on a multisection telescopic boom of a mobile crane. In particular, it relates to adjustable jib storage means to enable storage of the jib alongside the boom and to manually operable self-storing releasable pinning means for connecting the jib to the head of the boom.
2. Description of the Prior Art
Some mobile cranes have a multisection telescopic boom and a jib attachable to the point end of the boom to extend the working length of the boom. In some cranes, the jib is permanently connected to the boom head and is swingable into and out of working position as required. In other cranes, the jib is completely detachable and is stored alongside the boom base section on some types of jib storage means but can be readied for use by pivotally connecting one side of the jib base end to one side of the boom head, whereupon the jib can be swung into alignment with the boom and secured thereto. In some prior art arrangements, detachable pins or bolts are used to connect the jib to the boom head for pivoting purposes and for securing the boom extension in its in-use position. In other arrangements, the pins are part of a pin assembly and can be extended and retracted, as required, by means of a crank. U.S. Pat. No. 3,945,333 illustrates one prior art arrangement.